Bounds for error reduction with few quantum queries
APPROX'05/RANDOM'05 Proceedings of the 8th international workshop on Approximation, Randomization and Combinatorial Optimization Problems, and Proceedings of the 9th international conference on Randamization and Computation: algorithms and techniques
Quantum searching amidst uncertainty
UC'05 Proceedings of the 4th international conference on Unconventional Computation
ISAAC'05 Proceedings of the 16th international conference on Algorithms and Computation
Bounds for error reduction with few quantum queries
APPROX'05/RANDOM'05 Proceedings of the 8th international workshop on Approximation, Randomization and Combinatorial Optimization Problems, and Proceedings of the 9th international conference on Randamization and Computation: algorithms and techniques
Quantum money from hidden subspaces
STOC '12 Proceedings of the forty-fourth annual ACM symposium on Theory of computing
Systematic distillation of composite Fibonacci anyons using one mobile quasiparticle
Quantum Information & Computation
A quantum genetic algorithm with quantum crossover and mutation operations
Quantum Information Processing
Quantum Information Processing
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The standard quantum search lacks a feature, enjoyed by many classical algorithms, of having a fixed point, i.e. monotonic convergence towards the solution. Recently a fixed point quantum search algorithm has been discovered, referred to as the Phase-π/3 search algorithm, which gets around this limitation. While searching a database for a target state, this algorithm reduces the error probability from ε to ε2q+1 using q oracle queries, which has since been proved to be asymptotically optimal. A different algorithm is presented here, which has the same worst-case behavior as the Phase-π/3 search algorithm but much better average-case behavior. Furthermore the new algorithm gives ε2q+1 convergence for all integral q, whereas the Phase-π/3 search algorithm requires q to be (3n -1)/2 with n a positive integer. In the new algorithm, the operations are controlled by two ancilla qubits, and fixed point behavior is achieved by irreversible measurement operations applied to these ancillas. It is an example of how measurement can allow us to bypass some restrictions imposed by unitarity on quantum computing.